Modified break-action firearm

ABSTRACT

A break-action firearm for high caliber ammunition is described. In some arrangements, the firearm is a rifle. The higher caliber ammunition may be, for example, fifty caliber ammunition. The firearm includes a barrel that is hingedly coupled to a lower portion of the firearm. A latching mechanism secures the barrel in a firing position and releases the barrel from the firing position. The barrel includes a screw-on breech cap that is threadedly coupled to the end of the barrel. The breech cap includes a firing pin. When an ammunition cartridge is loaded into the barrel, the screw-on breech cap is installed, and the barrel is secured in the firing position, a user can pull a trigger that causes a firing hammer to hit the firing pin thereby firing the ammunition cartridge.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to U.S. Provisional PatentApplication No. 62/326,995, entitled “Modified Break-Action Firearm” andfiled Apr. 25, 2016. The contents of this application are incorporatedherein by reference and for all purposes.

TECHNICAL FIELD

The present application relates to break-action firearms.

BACKGROUND

Break-action firearms are firearms in which the barrel is hingedlyattached to the lower portion of the firearm (e.g., the portion of thefirearm having the firing mechanism, the breech face, the trigger, thegrip, etc.). The barrel can rotate away (“break” away) from the lowerportion to allow for the loading and unloading of ammunition cartridges.A hinge and latch mechanism is used to secure the barrel to the lowerportion during firing of the firearm. The break-action loading andunloading mechanisms can be found in shotguns, rifles, and pistols.

Many existing break-action firearms are not suitable for the highpressures and forces generated by high caliber ammunition, such as fiftycaliber ammunition and larger caliber ammunition. The higher pressuresand forces associated with high caliber ammunition can overstress thehinge and latch mechanism, which may render the firearm inoperable.Existing modifications of break-action firearms to accommodate highcaliber ammunition cause the hinge and latch mechanism to be morerobust, which causes a significant increase in weight of the firearm.Additionally, to account for the larger size of the high caliberammunition, the hinge pivot point must be moved farther away from thebreech face, which places the hinge and latch mechanism under evengreater stress. Excessive displacement between the barrel and breechleads to problems with extraction and can lead to case head separationof a cartridge. Notwithstanding the stress and strain factors, at acertain point the sheer size simply makes a traditional break-actionmechanism unwieldy for use with high caliber ammunition.

SUMMARY

One example embodiment relates to a firearm. The firearm includes alower portion having a grip, a trigger, and a firing hammer. The firearmincludes a barrel having a breech end and a muzzle end. The barrel ishingedly coupled to the lower portion such that the barrel is rotatablebetween a ready-to-fire position, in which the breech end is adjacent tothe lower portion, and a non-firing position, in which the breech end isdisplaced from the lower portion. The firearm further includes ascrew-on breech cap threadedly coupled to the breech end of the barrel.The screw-on breech cap has a firing pin.

Another example embodiment relates to a firearm. The firearm includes alower portion having a grip, a trigger, and a firing hammer. The firearmincludes a barrel having a breech end and a muzzle end. The barrel iscoupled to the lower portion such that the barrel is slidable between aready-to-fire position, in which the breech end is adjacent to the lowerportion, and a non-firing position, in which the breech end is displacedfrom the lower portion. The firearm further includes a screw-on breechcap threadedly coupled to the breech end of the barrel. The screw-onbreech cap has a firing pin.

A further example embodiment relates to a firearm. The firearm includesa lower portion having a grip, a trigger, and a firing hammer. Thefirearm includes a barrel having a breech end and a muzzle end. Thebarrel is coupled to the lower portion such that the barrel is rotatableand slidable between a ready-to-fire position, in which the breech endis adjacent to the lower portion, and a non-firing position, in whichthe breech end is displaced from the lower portion. The firearm furtherincludes a screw-on breech cap threadedly coupled to the breech end ofthe barrel. The screw-on breech cap has a firing pin such that thefiring pin cannot be struck by the firing hammer when the barrel is inin the non-firing position.

Another example embodiment relates to a firearm. The firearm includes alower portion having a grip, a trigger, and a firing hammer. The firearmincludes a barrel having a breech end and a muzzle end. The barrel iscoupled to the lower portion such that the barrel is rotatable between aready-to-fire position, in which the breech end is adjacent to the lowerportion, and a non-firing position, in which the breech end is displacedfrom the lower portion. The firearm further includes a breech having abreech body and a sliding plate slidably received within the breechbody. The sliding plate is hingedly coupled to the lower portion suchthat, when the barrel rotates between the ready-to-fire position and thenon-firing position, the sliding plate slides with respect to the breechbody.

These and other features, together with the organization and manner ofoperation thereof, will become apparent from the following detaileddescription when taken in conjunction with the accompanying drawings,wherein like elements have like numerals throughout the several drawingsdescribed below.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a side view of a firearm according to an exampleembodiment.

FIG. 2 shows a top view of the firearm of FIG. 1.

FIG. 3 shows a bottom view of the firearm of FIG. 1.

FIG. 4 shows a back view of the firearm of FIG. 1.

FIG. 5 shows a front view of the firearm of FIG. 1.

FIG. 6 shows a cross-sectional view of the firearm of FIG. 1 taken alongsection A-A of FIG. 2.

FIG. 7 shows a close-up cross-sectional view of the firearm of FIG. 1.

FIG. 8 shows a side view of the firearm of FIG. 1 having the barrelrotated away from the lower portion.

FIG. 9 shows a top view of the firearm of FIG. 1 in the position of FIG.8.

FIG. 10 shows a bottom view of the firearm of FIG. 1 in the position ofFIG. 8.

FIG. 11 shows a back view of the firearm of FIG. 1 in the position ofFIG. 8.

FIG. 12 shows a front view of the firearm of FIG. 1 in the position ofFIG. 8.

FIG. 13 shows a cross-sectional view of the firearm of FIG. 1 in theposition of FIG. 8 taken along section B-B of FIG. 9.

FIG. 14 shows a close-up cross-sectional view of the firearm of FIG. 1in the position of FIG. 8.

FIG. 15 shows a side view of the firearm of FIG. 1 having the barrelrotated away from the lower portion and having the screw-on breech capremoved from the barrel.

FIG. 16 shows a top view of the firearm of FIG. 1 in the position ofFIG. 15.

FIG. 17 shows a bottom view of the firearm of FIG. 1 in the position ofFIG. 15.

FIG. 18 shows a back view of the firearm of FIG. 1 in the position ofFIG. 15.

FIG. 19 shows a front view of the firearm of FIG. 1 in the position ofFIG. 15.

FIG. 20 shows a cross-sectional view of the firearm of FIG. 1 in theposition of FIG. 15 taken along section C-C of FIG. 16.

FIG. 21 shows a close-up cross-sectional view of the firearm of FIG. 1in the position of FIG. 15.

FIG. 22 shows a side view of a firearm according to another exampleembodiment.

FIG. 23 shows a cross-sectional view of the firearm of FIG. 22.

FIG. 24 shows a perspective view of the firearm of FIG. 23.

DETAILED DESCRIPTION

Referring to the figures generally, a break-action firearm is described.In some arrangements, the firearm is a rifle. In some arrangements, thefirearm is structured to fire high caliber ammunition. The high caliberammunition may be, for example, fifty caliber ammunition. In otherarrangements, the firearm is structured to fire lower caliber ammunition(e.g., ammunition that is of a lower caliber than fifty caliberammunition). The firearm includes a barrel that is hingedly coupled to alower portion of the firearm. A latching mechanism secures the barrel ina firing position and releases the barrel from the firing position. Thebarrel includes a screw-on breech cap that is threadedly coupled to thebreech end of the barrel. The breech cap includes a firing pin. When anammunition cartridge is loaded into the barrel, the screw-on breech capis installed, and the barrel is secured in the firing position, a usercan pull a trigger that causes a firing hammer to hit the firing pinthereby firing the ammunition cartridge.

Referring to FIGS. 1 through 7, views of a firearm 100 are shownaccording to an example embodiment. FIG. 1 shows a side view of thefirearm; FIG. 2 shows a top view of the firearm 100; FIG. 3 shows abottom view of the firearm 100; FIG. 4 shows a back view of the firearm100; FIG. 5 shows a front view of the firearm 100; FIG. 6 shows across-sectional view of the firearm 100 taken along section A-A of FIG.2; and FIG. 7 shows a close-up cross-sectional view of the firearm 100.In FIGS. 1-6, the firearm 100 is shown in the loaded and ready-to-fireposition. The firearm 100 generally includes a barrel assembly 102, alower portion 104, and a stock 106. The barrel assembly 102 includes abarrel having a breech end adjacent to the lower portion 104 and amuzzle end opposite the breech end (where a fired bullet leaves thebarrel assembly 102). In some arrangements, the barrel assembly 102includes additional components, such as a handguard, a forend, sights,and the like. The lower portion 104 includes a grip 108, a trigger 110,and a firing hammer 112 (shown best in FIGS. 6 and 7). The firing hammer112 is biased into the firing position (shown in FIG. 7). The firinghammer 112 can be pulled away from the barrel assembly 102 and into acocked position. When a user of the firearm 100 pulls the trigger 110,if the firing hammer 112 is in the cocked position, the firing hammer112 will return to the firing position of FIG. 7.

As shown in FIG. 7, the barrel assembly 102 includes a screw-on breechcap 114. The screw-on breech cap 114 is threadedly coupled to the breechend of the barrel assembly 102 (the rear of the barrel assembly 102).The screw-on breech cap 114 includes a firing pin 116. The firing pin116 is coupled to the screw-on breech cap 114. During firing of thefirearm 100, the firing pin 116 is configured to be struck by the firinghammer 112 such that a tip 118 of the firing pin 116 extends through thescrew-on breech cap 114 and strikes the rear of an ammunition cartridge120 loaded into the barrel assembly 102.

The barrel assembly 102 is hingedly coupled to a support 122 of thelower portion 104 via a pin 124. A spring loaded latch 126 secures alocking lug 128 of the barrel assembly 102 in the ready-to-fire position(shown in FIGS. 1 through 7). In the ready-to-fire position, the breechend of the barrel assembly 102 is adjacent to the lower portion 104. Thelocking lug 128 is positioned near the breech end of the barrel assembly102. The spring loaded latch 126 includes a locking detent 130 that isreceived in a lug detent 132 to secure the barrel assembly 102 in theready-to-fire position. When a user of the firearm 100 presses thespring loaded latch 126, the locking detent 130 is rotated out of thelug detent 132 such that the barrel assembly 102 can be rotated awayfrom the lower portion 104 about the pin 124 into a non-firing positionin which the breech end of the barrel assembly 102 is not adjacent to ortouching the lower portion 104 (e.g., as shown below in FIGS. 8 through14). When the barrel assembly 102 is secured to the lower portion 104,as shown in FIG. 7, the screw-on breech cap 114 and the breech end ofthe barrel assembly 102 are received in barrel seat 134. The loading andunloading of the firearm 100 are described in further detail below.

Referring to FIGS. 8 through 14, views of the firearm 100 having thebarrel assembly 102 rotated away from the lower portion 104 are shown.Specifically, FIG. 8 shows a side view of the firearm; FIG. 9 shows atop view of the firearm 100; FIG. 10 shows a bottom view of the firearm100; FIG. 11 shows a back view of the firearm 100; FIG. 12 shows a frontview of the firearm 100; FIG. 13 shows a cross-sectional view of thefirearm 100 taken along section B-B of FIG. 9; and FIG. 14 shows aclose-up cross-sectional view of the firearm 100. As shown in FIGS. 8through 14, the breech end of the barrel assembly 102 is rotated awayfrom the lower portion 104 about the pin 124 into a non-firing position(or conversely, the lower portion 104 is rotated away from thecenterline of the barrel assembly 102). In the non-firing position, thebreech end of the barrel assembly 102 is displaced from the lowerportion 104. As shown in FIGS. 8 through 14, the barrel assembly 102rotates (breaks) away from the lower portion 104 in a vertical manner(along the plane defined by section B-B or A-A; about the y-axis in astandard three-dimensional Cartesian coordinate system having an x-axis,a y-axis, and a z-axis, each of which are perpendicular to each other,wherein the x-axis is defined by the length of the barrel assembly 102).In an alternate arrangement, the barrel assembly 102 is rotated awayfrom the lower portion 104 in a horizontal manner (perpendicular to themanner shown in FIGS. 8 through 14; about the z axis in the standardthree-dimensional Cartesian coordinate system described above). Thescrew-on breech cap 114 rotates with the barrel assembly 102. Byrotating the barrel assembly 102, the screw-on breech cap 114 is exposed(displaced from the barrel seat 134) for removal from the barrelassembly 102 (e.g., to load or unload the firearm). The firing pin 116is displaced from the firing hammer 112 when the barrel assembly 102 isrotated to the non-firing position so that the firing pin 116 cannot beimpacted by the firing hammer 112 (shown best in FIG. 14) when thebarrel assembly 102 is in the non-firing position. In an alternatearrangement, the barrel assembly 102 breaks away from the lower portion104 through a sliding type action. In a further arrangement, the barrelassembly 102 breaks away from the lower portion 104 through acombination sliding and pivoting type action. In each of theabove-described alternate break actions, the barrel assembly 102 can befixed in place with respect to the lower portion 104 by moving thebarrel assembly 102 back towards the lower portion 104 to engage thespring loaded latch 126 or other type of latch. It should be understoodthat, in certain embodiments, the firearm 100 includes a latch that isdifferent than the spring loaded latch 126 illustrated in FIGS. 8-14.For example, some embodiments utilize a spring loaded latch that isengaged via a sliding action. In other embodiments, the firearm 100includes a spring loaded detent that engages a complimentary feature tofix the barrel assembly 102 in place with respect to the lower portion104.

Referring to FIGS. 15 through 21, views of the firearm 100 having thebarrel assembly 102 rotated away from the lower portion 104 and thescrew-on breech cap 114 removed from the barrel assembly 102 are shown.Specifically, FIG. 15 shows a side view of the firearm; FIG. 16 shows atop view of the firearm 100; FIG. 17 shows a bottom view of the firearm100; FIG. 18 shows a back view of the firearm 100; FIG. 19 shows a frontview of the firearm 100; FIG. 20 shows a cross-sectional view of thefirearm 100 taken along section C-C of FIG. 16; and FIG. 21 shows aclose-up cross-sectional view of the firearm 100. The screw-on breechcap 114 can be removed from the barrel assembly 102 by unscrewing thescrew-on breech cap 114 from the breech end of the barrel assembly 102.In an alternative arrangement, the screw-on breech cap 114 is threadedlycoupled to a barrel extension or another device coupled to the barrelassembly 102. In various embodiments, the screw-on breech cap 114, thebarrel assembly 102, and/or the barrel extension includes interruptedthreads. When the screw-on breech cap 114 is removed, the cartridge 120(or casing remaining after firing the cartridge 120) can be removed, anda new cartridge can be loaded into the barrel assembly 102. In somearrangements, the screw-on breech cap 114 includes an extractionmechanism that pulls the cartridge 120 (or casing) out of the barrelassembly 102 as the screw-on breech cap 114 is removed from the barrelassembly 102. The screw-on breech cap 114 can be threadedly secured tothe barrel assembly 102, and the barrel assembly 102 can be rotated backinto the ready-to-fire position of FIGS. 1 through 7 to fire the loadedcartridge 120.

In some arrangements, the screw-on breech cap 114 is substituted for abolt, a sliding plate (e.g., as described below with respect to FIGS. 22through 24), a falling block, or any other barrel breech lockingmechanism that can be manipulated after the barrel assembly 102 isrotated away from the lower portion 104 (once the action is “broken”).In such arrangements, the breech locking mechanism may include a leveror other mechanical device that allows the user to manipulate the breechlocking mechanism (e.g., to load and unload the cartridge 120). In somearrangements, the screw-on breech cap 114 or alternative barrel breechlocking mechanism includes wrench flats, holes, other protrusions,and/or cavities to aid in removal of the screw-on breech cap 114 oralternative barrel breech locking mechanism by a tool or by the user'sfingers.

In some arrangements, the barrel assembly 102 is fitted with an upperreceiver assembly 136. The upper receiver assembly 136 may be a customupper receiver assembly or an upper receiver assembly from an existingfirearm, such as an AR-15 or the like. The upper receiver assembly 136provides a coupling surface for accessories, such as sights, lasers,bipods, and the like.

Referring to FIGS. 22 through 24, views of a firearm 2200 are shownaccording to another example embodiment. FIG. 22 shows a side view ofthe firearm 2200; FIG. 23 shows a cross-sectional view of the firearm2200; and FIG. 24 shows a perspective view of the firearm 2200. Thefirearm 2200 is similar to the firearm 100 of FIGS. 1 through 21. Thefirearm 2200 generally includes a barrel assembly 2202, a lower portion2204, and a stock 2206. The barrel assembly 2202 includes a barrelhaving a breech end adjacent to the lower portion 2204 and a muzzle endopposite the breech end (where a fired bullet leaves the barrel assembly2202). In some arrangements, the barrel assembly 2202 includesadditional components, such as a handguard, a forend, sights, and thelike. The lower portion 2204 includes a grip 2208, a trigger (notshown), and a firing hammer 2210 (shown best in FIG. 24). When a user ofthe firearm 2200 pulls the trigger, if the firing hammer 2210 is in thecocked position, the firing hammer 2210 will move to the firing positionin a similar manner as described above with respect to the firearm 100.

The firearm 2200 differs from the firearm 100 primarily in that thescrew-on breech cap 114 of the firearm 100 is replaced with a breech2212 in the firearm 2200. The breech 2212 is coupled to the breech endof the barrel assembly 2202. The breech includes a breech body 2214 anda sliding plate 2216. The sliding plate 2216 is received in a slot inthe breech body 2214. The barrel assembly 2202 is hingedly coupled tothe lower portion 2204 through a first hinge 2218. The sliding plate2216 is hingedly coupled to the lower portion 2204 through a secondhinge 2220. In some arrangements, the second hinge 2220 is a linkagesystem that includes a link that is hingedly coupled to both the lowerportion 2204 and the sliding plate 2216. Accordingly, when the barrelassembly 2202 rotates away from the lower portion 2204 about the firsthinge 2218 (to the non-firing position in a similar manner as describedabove with respect to the firearm 100), the sliding plate 2216 slideswith respect to the breech body 2214 to an open position, therebyproviding access to an opening 2222 in the breech body 2214 to load acartridge 120 or remove the cartridge 120 (or casing after firing thecartridge 120). When the barrel assembly 2202 rotates towards the lowerportion 2204 about the first hinge 2218 (to the ready-to-fire positionin a similar manner as described above with respect to the firearm 100),the sliding plate 2216 slides with respect to the breech body 2214 to aclosed position so as to substantially close off the opening 2222 in thebreech body 2214 thereby securing a loaded cartridge 120 in the barrelassembly 2202. In some embodiments, the firearm 2200 includes anextraction mechanism (not shown) structured to pull an ammunitioncartridge from the barrel upon the sliding plate 2216 being slid to theopen position.

In some embodiments, the sliding plate 2216 is not hingedly to the lowerportion 2204 through the second hinge 2220. Instead, in suchembodiments, the firearm 2200 includes a lever (not shown) operativelycoupled to the sliding plate 2216. The sliding plate 2216 can beslidably actuated between the open position and the closed position by auser via the lever.

It should be noted that any use of the term “example” herein to describevarious embodiments is intended to indicate that such embodiments arepossible examples, representations, and/or illustrations of possibleembodiments (and such term is not intended to connote that suchembodiments are necessarily extraordinary or superlative examples).

The terms “coupled” and the like as used herein mean the joining of twomembers directly or indirectly to one another. Such joining may bestationary (e.g., permanent) or moveable (e.g., removable orreleasable). Such joining may be achieved with the two members or thetwo members and any additional intermediate members being integrallyformed as a single unitary body with one another or with the two membersor the two members and any additional intermediate members beingattached to one another.

References herein to the positions of elements (e.g., “top,” “bottom,”“above,” “below,” “lower,” “upper,” “front,” “back,” etc.) are merelyused to describe the orientation of various elements in the FIGURES. Itshould be noted that the orientation of various elements may differaccording to other example embodiments, and that such variations areintended to be encompassed by the present disclosure.

It is important to note that the construction and arrangement of thevarious example embodiments are illustrative only. Although only a fewembodiments have been described in detail in this disclosure, thoseskilled in the art who review this disclosure will readily appreciatethat many modifications are possible (e.g., variations in sizes,dimensions, structures, shapes and proportions of the various elements,values of parameters, mounting arrangements, use of materials, colors,orientations, etc.) without materially departing from the novelteachings and advantages of the subject matter described herein. Forexample, elements shown as integrally formed may be constructed ofmultiple parts or elements, the position of elements may be reversed orotherwise varied, and the nature or number of discrete elements orpositions may be altered or varied. The order or sequence of any processor method steps may be varied or re-sequenced according to alternativeembodiments. Additionally, features from particular embodiments may becombined with features from other embodiments as would be understood byone of ordinary skill in the art. Other substitutions, modifications,changes and omissions may also be made in the design, operatingconditions and arrangement of the various example embodiments withoutdeparting from the scope of the present invention.

What is claimed is:
 1. A firearm comprising: a lower portion having agrip, a trigger, and a firing hammer; a barrel having a breech end and amuzzle end, the barrel hingedly coupled to the lower portion such thatthe barrel is rotatable between a ready-to-fire position in which thebreech end is adjacent to the lower portion, and a non-firing positionin which the breech end is displaced from the lower portion; and ascrew-on breech cap threadedly coupled to the breech end of the barrel,the screw-on breech cap including a firing pin.
 2. The firearm of claim1, wherein the screw-on breech cap rotates with the barrel when thebarrel is rotated to the non-firing position so as to expose thescrew-on breech cap for removal from the barrel.
 3. The firearm of claim2, wherein the firing pin of the screw-on breach cap is displaced fromthe firing hammer when the barrel is rotated to the non-firing positionsuch that the firing pin cannot be struck by the firing hammer when thebarrel is in the non-firing position
 4. The firearm of claim 1, whereinthe lower portion includes a spring loaded latch configured to secure alocking lug of the barrel when the barrel is in the ready-to-fireposition.
 5. The firearm of claim 1, wherein the barrel is structured toreceive a fifty caliber ammunition cartridge.
 6. The firearm of claim 1,wherein the screw-on breech cap includes wrench flats or protrusionsstructured to assist with removal of the screw-on breech cap from thebreech end of the barrel.
 7. The firearm of claim 1, wherein thescrew-on breech cap further includes an extraction mechanism structuredto pull an ammunition cartridge from the barrel upon removal of thescrew-on breech cap from the barrel.
 8. The firearm of claim 1, whereina length of the barrel defines an x-axis when the barrel is in theready-to-fire position, wherein a y-axis is perpendicular to the x-axis,and a z-axis is perpendicular to the x-axis and the y-axis.
 9. Thefirearm of claim 8, wherein the barrel rotates with respect to the lowerportion about the y-axis.
 10. The firearm of claim 8, wherein the barrelrotates with respect to the lower portion about the z-axis.
 11. Thefirearm of claim 1, further comprising an upper receiver assemblycoupled to the barrel.
 12. A firearm comprising: a lower portion havinga grip, a trigger, and a firing hammer; a barrel having a breech end anda muzzle end, the barrel coupled to the lower portion such that thebarrel is slidable between a ready-to-fire position in which the breechend is adjacent to the lower portion, and a non-firing position in whichthe breech end is displaced from the lower portion; and a screw-onbreech cap threadedly coupled to the breech end of the barrel, thescrew-on breech cap including a firing pin.
 13. The firearm of claim 12,wherein the screw-on breech cap slides with the barrel when the barrelis slid to the non-firing position so as to expose the screw-on breechcap for removal from the barrel.
 14. The firearm of claim 13, whereinthe firing pin of the screw-on breach cap is displaced from the firinghammer when the barrel is slid to the non-firing position such that thefiring pin cannot be struck by the firing hammer when the barrel is inthe non-firing position.
 15. The firearm of claim 12, wherein thescrew-on breech cap further includes an extraction mechanism structuredto pull an ammunition cartridge from the barrel upon removal of thescrew-on breech cap from the barrel.
 16. A firearm comprising: a lowerportion having a grip, a trigger, and a firing hammer; a barrel having abreech end and a muzzle end, the barrel coupled to the lower portionsuch that the barrel is slidable and rotatable between a ready-to-fireposition in which the breech end is adjacent to the lower portion, and anon-firing position in which the breech end is displaced from the lowerportion; and a screw-on breech cap threadedly coupled to the breech endof the barrel, the screw-on breech cap including a firing pin such thatthe firing pin cannot be struck by the firing hammer when the barrel isin in the non-firing position.
 17. A firearm comprising: a lower portionhaving a grip, a trigger, and a firing hammer; a barrel having a breechend and a muzzle end, the barrel hingedly coupled to the lower portionsuch that the barrel is rotatable between a ready-to-fire position inwhich the breech end is adjacent to the lower portion, and a non-firingposition in which the breech end is displaced from the lower portion;and a breech having a breech body and a sliding plate slidably receivedwithin the breech body, the sliding plate hingedly coupled to the lowerportion such that, when the barrel rotates between the ready-to-fireposition and the non-firing position, the sliding plate slides withrespect to the breech body.
 18. The firearm of claim 17, furthercomprising a link hingedly coupling the sliding plate and the lowerportion, the link structured to slide the sliding plate to a closedposition when the barrel is rotated to the ready-to-fire position. 19.The firearm of claim 18, wherein the link is further structured to slidethe sliding plate to an open position when the barrel is rotated to thenon-firing position.
 20. The firearm of claim 19, further comprising anextraction mechanism structured to pull an ammunition cartridge from thebarrel upon the sliding plate being slid to the open position.